If you have worried about having some alternative source of power during power outages but don't want to keep a gas-powered generator around, this new human-powered generator from Freeplay may be just the thing.
It uses foot power to generate enough electricity to charge cellphones and laptops and to run or charge other small wattage devices. It also comes with jumper cables so that you can jump start (literally, by jumping up and down on the pedal of this thing) a car. It comes with a cigarette lighter style 12 volt adapter so it can be used with any device that has a 12 volt charger.
This would be an ideal alternative energy source for someone that lives in a high rise apartment or condo where it is not possible to store a gas powered generator (and a can of gasoline).